Yes sir, The carb that I replaced was a Holley street avenger and it worked fine. It was 12 years old and I just thought that I better put a new one on while I can still find a carb for my 76 G20. Every thing was fine as it was, bought a new 4150 600 cfm, replaced the intake gasket (as usual) put the carb on and idle went to 1400 and could never get it down. I then replaced all air lines, air caps, replaced the gasket again, started it up same problem did not change anything on idle. The owner of Coopers Garage locally had the same problem with a new Holley of a Mustang rebuild, his dad the owner for 60 years has a 60s vette, put a new Holley on it, same thing, twice after retuning the carb. I gave my new carb to a manager at the local Oreilly's auto parts and I bought another Street avenger 570 cfm exactly like the one that I was replacing. Replace the carb (new gasket) fired it up same problem. Tempted to put the original back on, start it up and see what happens. The cold temps just came to Detroit area so any carb swap may not happen for a while, I do not want to do the work again, but if I put the old one back on and it works fine then I know that it is the new Holley.